I have been using this product for sciatica for over a year now and my pain returns if I stop it, even for a few days. This brand was recommended by my acupuncturist because of its efficacy and purity and I am living proof that it works. IHERB's price on this is the best I've seen.

My husband had a stroke, and received a tPA ("clot busting" drug) in the emergency room. A tPA will indeed break down a clot, but if you get another one, you need another tPA, and they told me it costs $5000 to pop the cap on one of those vials. You can also hemorrhage from these drugs.
I learned that nattokinase has the property of digesting clots for many hours, so now we include Nutricology NattoZyme in his daily regimen. As a heart transplant recipient, he has invasive tests done on a regular basis. After he is finished with a left or right ventricular catheterization, as soon as he's awake enough to swallow, I give him NattoZyme to protect him from clots that may have formed from the procedure.
I'm happy with NattoZyme.